Conventionally, information analysis techniques are available for analyzing information acquired by a probe vehicle to understand traffic conditions such as road traffic congestion or find vehicles parked on roads or streets. One of such techniques is for detecting not-running vehicles among the vehicles found on the road, from a captured image of the surroundings by an imaging device mounted on a probe vehicle.
However, such conventional techniques have difficulties in accurately determining whether the not-running vehicle is parked or temporarily stopped e.g., to wait for a traffic light to change.